Transmission of Bundled ACK/NAK Bits

ABSTRACT

This invention is applicable to wireless communication between a user equipment (UE) and a base station using frames where at least one uplink (UL) is assigned a subframe to respond to a plurality of DL assigned subframes. This invention is an improvement in the acknowledge (ACK) or non-acknowledge (NAK) response by the UE. The UE generates an ACK or NAK dependent upon whether a DL communication is correctly received. For an UL subframe assigned to respond to communications on plural DL subframes, the UE logically combines plural ACK/NAK responses into a single bundled response for transmission to the base station. This logical combining produces a bit in a first digital state if all said responses are ACKs and in a second opposite digital state if any response is a NAK.

CLAIM OF PRIORITY

This application claims priority under 35 U.S.C. 119(e)(1) to U.S.Provisional Application No. 61/045,730 filed Apr. 17, 2008, U.S.Provisional Application No. 61/046,538 filed Apr. 21, 2008, U.S.Provisional Application No. 61/048,733 filed Apr. 29, 2008, U.S.Provisional Application No. 61/075,061 filed Jun. 24, 2008 and U.S.Provisional Application No. 61/086,834 filed Aug. 7, 2008.

TECHNICAL FIELD OF THE INVENTION

The technical field of this invention is transmission of control signalsin wireless telephony.

BACKGROUND OF THE INVENTION

FIG. 1 shows an exemplary wireless telecommunications network 100. Theillustrative telecommunications network includes base stations 101, 102and 103, though in operation, a telecommunications network necessarilyincludes many more base stations. Each of base stations 101, 102 and 103are operable over corresponding coverage areas 104, 105 and 106. Eachbase station's coverage area is further divided into cells. In theillustrated network, each base station's coverage area is divided intothree cells. Handset or other user equipment (UE) 109 is shown in Cell A108. Cell A 108 is within coverage area 104 of base station 101. Basestation 101 transmits to and receives transmissions from UE 109. As UE109 moves out of Cell A 108 and into Cell B 107, UE 109 may be handedover to base station 102. Because UE 109 is synchronized with basestation 101, UE 109 can employ non-synchronized random access toinitiate handover to base station 102.

Non-synchronized UE 109 also employs non-synchronous random access torequest allocation of up-link 111 time or frequency or code resources.If UE 109 has data ready for transmission, which may be traffic data,measurements report, tracking area update, UE 109 can transmit a randomaccess signal on up-link 111. The random access signal notifies basestation 101 that UE 109 requires up-link resources to transmit the UE'sdata. Base station 101 responds by transmitting to UE 109 via down-link110, a message containing the parameters of the resources allocated forUE 109 up-link transmission along with a possible timing errorcorrection. After receiving the resource allocation and a possibletiming advance message transmitted on down-link 110 by base station 101,UE 109 optionally adjusts its transmit timing and transmits the data onup-link 111 employing the allotted resources during the prescribed timeinterval.

FIG. 2 shows the Evolved Universal Terrestrial Radio Access (E-UTRA)time division duplex (TDD) Frame Structure. Different subframes areallocated for downlink (DL) or uplink (UL) transmissions. Table 1 showsapplicable DL/UL subframe allocations.

TABLE 1 Con- Switch-point Subframe number figuration periodicity 0 1 2 34 5 6 7 8 9 0  5 ms D S U U U D S U U U 1  5 ms D S U U D D S U U D 2  5ms D S U D D D S U D D 3 10 ms D S U U U D D D D D 4 10 ms D S U U D D DD D D 5 10 ms D S U D D D D D D D 6 10 ms D S U U U D S U U D

One interesting property of TDD is that the number of UL and DLsubframes can be different. In the configurations where there are moreDL subframes than UL subframes, multiple DL subframes are associatedwith one single UL subframe for transmission of corresponding controlsignal. For example, for each dynamically scheduled transmission in theDL subframes, acknowledge and non-acknowledge (ACK/NAK) bits need to betransmitted in an associated UL subframe to support proper hybridautomatic repeat request (HARQ) operation. If UE 109 is scheduled in amultiple of DL subframes all of which are associated with one single ULsubframe, UE 109 needs to transmit multiple ACK/NAK bits in that singleUL subframe.

SUMMARY OF THE INVENTION

This invention is applicable to wireless communication between a userequipment (UE) and a base station using frames where at least one uplink(UL) is assigned a subframe to respond to a plurality of DL assignedsubframes. This invention is an improvement in the acknowledge (ACK) ornon-acknowledge (NAK) response by the UE. The UE generates an ACK or NAKdependent upon whether a DL communication is correctly received. For anUL subframe assigned to respond to communications on plural DLsubframes, the UE logically combines plural ACK/NAK responses into asingle bundled response for transmission to the base station. Thislogical combining produces a bit in a first digital state if allresponses are ACKs and in a second opposite digital state if anyresponse is a NAK.

BRIEF DESCRIPTION OF THE DRAWINGS

These and other aspects of this invention are illustrated in thedrawings, in which:

FIG. 1 is a diagram of a communication system of the prior art relatedto this invention having three cells;

FIG. 2 shows the Evolved Universal Terrestrial Radio Access (E-UTRA) TDDFrame Structure of the prior art;

FIG. 3 shows the case of pure bundling for multiple ACK/NAK bits arebundled into 1 or 2 bits;

FIG. 4 illustrates an example of spatial sub-bundling for a DL to ULsubframe ratio of 4;

FIG. 5 illustrates possible DTX/NAK combinations for the case of a DL toUL ratio of 2;

FIG. 6 illustrates another possible set of DTX/NAK combinations for thecase of a DL to UL ratio of 2; and

FIG. 7 illustrates possible DTX/NAK combinations for the case of a DL toUL ratio of 3.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

In 3GPP (Third Generation Partnership Project) Long Term Evolution(LTE), an UL subframe can be associated with 1, 2, 3, 4, or 9 DLsubframes. Thus it is possible to have 18 ACK/NAK bits in one ULsubframe depending on the number of data streams in the DLtransmissions.

The basic design principle of this invention transmits multiple ACK/NAKbits on one of the ACK/NAK channels that UE has correctly received theDL packets using physical uplink control channel (PUCCH) format 1 a or 1b. Using this invention requires no additional PUCCH resource to bereserved for the transmission of multiple ACK/NAK bits. In accordancewith this invention plural such ACK/NAK bits may be combined or bundledfor transmission.

This invention proposes several design rules for multiple ACK/NAKtransmission.

Rule 1: The maximum number of multiple ACK/NAK bits of one UE in an ULsubframe is 4.

Rule 2: UEs employing DL Multiple Input, Multiple Output (MIMO)operation bundle the ACK/NAK bits associated with multiple data streamsinto a single ACK/NAK bit.

Rule 3: When one UL subframe is associated with nine DL subframes, UEsbundles the ACK/NAK bits in the first four or five DL subframes into 1or 2 bits, then bundle the ACK/NAK bits in the last five or four DLsubframes into the 1 or 2 ACK/NAK bits. The bundling selection dependson whether DL transmission mode is either single input, multiple output(SIMO) or MIMO.

Table 2 lists the multiple ACK/NAK transmission configurations of thisinvention.

TABLE 2 Number of DL subframes associated Number of ACK/NAK bits withone UL subframe SIMO MIMO 1 1 2 2 2 4 3 3 3 4 4 4 9 2 4

For UEs having one associated DL subframe, the same ACK/NAK transmissionas in frequency division duplex (FDD) can be used with physical uplinkcontrol channel (PUCCH) format 1 a or 1 b. For UEs having two associatedDL subframes, the invention supports explicit transmission of either 2or 4 ACK/NAK. It is also possible to have 3 ACK/NAK bits in one ULsubframe having two associated DL subframes. In this case thetransmission of one DL subframe is SIMO and the other is MIMO. For UEshaving three or four associated DL subframes, the ACK/NAK bitscorresponding to MIMO transmission in any DL subframe are bundled intoone ACK/NAK bit. This reduces the maximum number of multiple ACK/NAKbits. When one UL subframe is associated with nine DL subframes, UEsbundle the ACK/NAK bits in the first four or five DL subframes into 1 or2 bits, then bundle the ACK/NAK bits in the last five or four DLsubframes into the 1 or 2 ACK/NAK bits. The bundling selection dependson whether DL transmission mode is either SIMO or MIMO.

FIG. 3 shows the case of pure bundling, where the multiple ACK/NAK bitsare bundled into 1 or 2 bits, depending on the number of DL spatialcodewords. The manner of bundling depends upon the coding of the ACK/NAKbit. These plural bits are combined so that a single NAK toggles thebundled bit. Thus if ACK=1 and NAK=0, the individual ACK/NAK bits areANDed to produce the bundled bit. A single NAK would cause a 0 resultinterpreted as a NAK. If ACK=0 and NAK=1, the individual ACK/NAK bitsare ORed to produce the bundled bit. A single NAK would cause a 1 resultinterpreted as a NAK. In either case all ACKs result in a combinedACK/NAK having a first digital state and any NAK results in a combinedACK/NAK having an opposite second digital state. FIG. 3 a illustratesbundling the ACK/NAK response to four data streams including data stream301 of DL subframe 1, data stream 302 of DL subframe 2, data stream 303of DL subframe 3 and data stream 304 of DL subframe 4 into a singleACK/NAK bit 305. FIG. 3 b illustrates bundling when the data streamshave differing length. The data transmitted in DL subframe 1 includesdata stream 311 and data stream 321. The data transmitted in DL subframe2 includes data stream 312 and data stream 322. The data transmitted inDL subframe 3 includes only data stream 313. The data transmitted in DLsubframe 4 includes data stream 313 and data stream 324. A first bit 315of the bundled ACK/NAK combines individual ACK/NAK bits for data stream1 of DL subframes 1, 2, 3 and 4. A second bit 325 of the bundled ACK/NAKcombines individual ACK/NAK bits for data stream 2 of DL subframes 1, 2and 4.

FIG. 4 illustrates an example of spatial sub-bundling for a DL to ULsubframe ratio of 4. In this example ACK/NAK sub-bundling is performedacross MIMO (spatial multiplexing) codewords per DL subframe. Data in DLsubframe 1 including data stream 401 and data stream 411 are bundled inACK/NAK bit 421. Data in DL subframe 2 including data stream 402 anddata stream 412 are bundled in ACK/NAK bit 422. Data in DL subframe 3including data stream 403 and data stream 413 are bundled in ACK/NAK bit423. Data in DL subframe 4 including data stream 404 and data stream 414are bundled in ACK/NAK bit 424.

This invention supports ACK/NAK bundling to enable coverage. Adisadvantage is that ACK/NAK bundling generally causes unnecessaryretransmission. All packets in the bundling window are retransmitted ifthere is one packet received incorrectly. This is required because thebase station cannot determine which DL transmission in the ACK/NAKbundle was incorrectly received and generate a NAK response. ThusACK/NAK bundling across system reduces DL throughput. Therefore TDDshould support both multiple ACK/NAK transmission and ACK/NAK bundling.This invention proposes details of a method for multiple ACK/NAKtransmission in TDD.

As noted in Table 2, a UE can transmit 2, 3, or 4 ACK/NAK bits in one ULsubframe. This invention includes detailed schemes for suchtransmission.

In the following description the ACK/NAK bits are denoted as (b₁, b₂, .. . , b_(n)), where n=2, 3, or 4. The ACK/NAK channels associated withdifferent DL subframes are denoted as (h₁, h₂, . . . , h_(n)), wheren=2, 3, or 4. A bit b_(i) is the ACK/NAK bit of the i-th DL subframecorresponding to the same UL subframe. A channel h_(i) is the ACK/NAKchannel for the i-th DL subframe corresponding to the same UL subframe.Table 3 shows one example of QPSK symbols. Note that “j” is the complexnumber √{square root over (−1)}. Other QPSK symbol mappings arepossible.

TABLE 3 QPSK Symbols Q₁: 00 −1 Q₂: 01  j Q₃: 10 −j Q₄: 11  1

Table 4 lists an example coding of two bits (b₁, b₂) when the ACK/NAKbits are transmitted on two channels.

TABLE 4 (A/N Channel, b₂ b₁ QPSK symbol) 0, 0 (h₂, Q₁) 0, 1 (h₂, Q₂) 1,0 (h₁, Q₃) 1, 1 (h₁, Q₄) or DTX

Table 5 lists an example coding of three bits (b₁, b₂, b₃) when theACK/NAK bits are transmitted on three channels.

TABLE 5 (A/N Channel, b₃ b₂ b₁ QPSK symbol) 0, 0, 0 (h₃, Q₁) 0, 0, 1(h₃, Q₂) 0, 1, 0 (h₃, Q₃) 0, 1, 1 (h₃, Q₄) 1, 0, 0 (h₂, Q₁) 1, 0, 1 (h₂,Q₄) 1, 1, 0 (h₁, Q₁) 1, 1, 1 (h₁, Q₄) or DTX

Table 6 lists an example coding of four bits (b₁, b₂, b₃, b₄) when theACK/NAK bits are transmitted on four channels.

TABLE 6 (A/N Channel, b₄ b₃ b₂ b₁ QPSK symbol) 0, 0, 0. 0 (h₂, Q₁) 0, 0,0, 1 (h₂, Q₃) 0, 0, 1, 0 (h₄, Q₁) 0, 0, 1, 1 (h₄, Q₃) 0, 1, 0, 0 (h₁,Q₂) 0, 1, 0, 1 (h₄, Q₂) 0, 1, 1, 0 (h₁, Q₃) 0, 1, 1, 1 (h₄, Q₄) 1, 0, 0,0 (h₃, Q₁) 1, 0, 0, 1 (h₃, Q₂) 1, 0, 1, 0 (h₃, Q₃) 1, 0, 1, 1 (h₃, Q₄)1, 1, 0, 0 (h₂, Q₂) 1, 1, 0, 1 (h₂, Q₄) 1, 1, 1, 0 (h₁, Q₁) 1, 1, 1, 1(h₁, Q₄) or DTX

Tables 4 to 6 illustrate examples only and other mapping scheme arepossible. These examples assume that a 0 represents ACK and a 1represents NAK or DTX. Note a DTX indicates that the UE missed DL grantin that DL subframe. The notation of (h_(i), Q_(j)) indicatestransmitting QPSK symbol Q_(j) on ACK/NAK channel h_(i). DTX and NAK aretreated similarly.

Tables 4 to 6 illustrate sub-bundling across MIMO codewords, for DL/ULratio of 3 or 4. Thus there is one ACK/NAK bit per DL subframe. When aUE produces an ACK (in this example 0) on DL subframe j, then the UEmust have decoded the corresponding DL grant correctly. Therefore, theACK/NAK channel h_(j) corresponding to DL subframe j is alwaysavailable. When using MIMO operation, the UE can derive two ACK/NAKchannels corresponding to a DL subframe. Alternatively stated, a DLgrant for MIMO operation consists of at least two control channelelements (CCEs). Therefore, for MIMO operation, there could be multipleACK/NAK channels from the one DL subframe.

When the ACK/NAK bundles all 1s, that is for any combination of at leastone DTX or NAK, the UE has two options. The UE can transmit ACK/NAK DTXby transmitting nothing. Alternatively the UE can transmit a QPSK symbolon ACK/NAK channel 1 if available.

For concurrent transmission of multiple ACK/NAK bits and a channelquality indicator (CQI), the UE bundles all ACK/NAK bits into 1 or 2ACK/NAK bits. The UE uses the concurrent transmission scheme of bundledACK/NAK and CQI.

For concurrent transmission of multiple ACK/NAK bits and SRI, the UEbundles all ACK/NAK bits into 1 or 2 ACK/NAK bits. The UE uses theconcurrent transmission scheme of bundled ACK/NAK and SRI.

The UE may use Downlink Assignment Index (DAI) to infer whether itmissed any DL grant in the bundling window. When the UE detects that itmisses at least one DL grant, it can transmit DTX by transmit nothing.

DTX and NAK share a common state in this invention. This limits themaximum number of ACK/NAK bits and improves the transmissionreliability. Thus the all 0 case in Tables 4 to 6 represents severalDTX/NAK combinations.

Tables 7 to 9 illustrate alternative examples of the codings listed inTables 4 to 6. Table 7 lists another example coding of two bits (b₂, b₂)when the ACK/NAK bits are transmitted on two channels.

TABLE 7 (A/N Channel, b₂ b₁ QPSK symbol) 0, 0 (h₂, Q₁) 0, 1 (h₂, Q₄) 1,0 (h₁, Q₃) 1, 1 (h₁, Q₂) or DTX

Table 8 lists another example coding of three bits (b₁, b₂, b₃) when theACK/NAK bits are transmitted on three channels.

TABLE 8 (A/N Channel, b₃ b₂ b₁ QPSK symbol) 0, 0, 0 (h₃, Q₁) 0, 0, 1(h₃, Q₂) 0, 1, 0 (h₃, Q₃) 0, 1, 1 (h₃, Q₄) 1, 0, 0 (h₂, Q₁) 1, 0, 1 (h₂,Q₄) 1, 1, 0 (h₁, Q₃) 1, 1, 1 (h₁, Q₂) or DTX

Table 9 lists another example coding of four bits (b₁, b₂, b₃, b₄) whenthe ACK/NAK bits are transmitted on four channels.

TABLE 9 (A/N Channel, b₄ b₃ b₂ b₁ QPSK symbol) 0, 0, 0, 0 (h₂, Q₁) 0, 0,0, 1 (h₂, Q₄) 0, 0, 1, 0 (h₄, Q₁) 0, 0, 1, 1 (h₄, Q₃) 0, 1, 0, 0 (h₁,Q₂) 0, 1, 0, 1 (h₄, Q₂) 0, 1, 1, 0 (h₁, Q₃) 0, 1, 1, 1 (h₄, Q₄) 1, 0, 0,0 (h₃, Q₁) 1, 0, 0, 1 (h₃, Q₂) 1, 0, 1, 0 (h₃, Q₃) 1, 0, 1, 1 (h₃, Q₄)1, 1, 0, 0 (h₂, Q₂) 1, 1, 0, 1 (h₂, Q₃) 1, 1, 1, 0 (h₁, Q₁) 1, 1, 1, 1(h₁, Q₄) or DTX

Table 10 shows the supported number of ACK/NAK bits, for different DL/ULratios in another embodiment. The maximum number of multiple ACK/NAKbits is 4. For DL MIMO mode with a DL to UL ratio of 3 or 4, ACK/NAKsub-bundling reduces the number of multiple ACK/NAK bits. This inventionincluded 2 states for each ACK/NAK bit. These are an ACK and a NAK/DTX.For the DL subframes in which the UE does not detect DL grant, NAK istransmitted for the corresponding DL subframes.

TABLE 10 Number of DL Maximum number of ACK/NAK bits subframesNon-spatial Spatial associated multiplexing multiplexing with one ULPure No Pure Spatial Sub- subframe Bundling Bundling Bundling bundling 21 2 2 2 3 1 3 2 3 4 1 4 2 4 9 1 4 2 4

Table 11 lists an example coding of two bits (b₁, b₂) when the ACK/NAKbits are transmitted on two channels.

TABLE 11 (A/N Channel, b₂ b₁ QPSK symbol) 1, 1 (h₂, Q₁) 1, 0 (h₂, Q₄) 0,1 (h₁, Q₃) 0, 0 DTX

Table 12 lists an example coding of three bits (b₂, b₂, b₃) when theACK/NAK bits are transmitted on three channels.

TABLE 12 (A/N Channel, b₃ b₂ b₁ QPSK symbol) 1, 1, 1 (h₃, Q₁) 1, 1, 0(h₃, Q₂) 1, 0, 1 (h₃, Q₃) 1, 0, 0 (h₃, Q₄) 0, 1, 1 (h₂, Q₁) 0, 1, 0 (h₂,Q₄) 0, 0, 1 (h₁, Q₃) 0, 0, 0 DTX

Table 13 lists an example coding of four bits (b₁, b₂, b₃, b₄) when theACK/NAK bits are transmitted on four channels.

TABLE 13 (A/N Channel, b₄ b₃ b₂ b₁ QPSK symbol) 1, 1, 1, 1 (h₂, Q₁) 1,1, 1, 0 (h₂, Q₄) 1, 1, 0, 1 (h₄, Q₁) 1, 1, 0, 0 (h₄, Q₃) 1, 0, 1, 1 (h₁,Q₂) 1, 0, 1, 0 (h₄, Q₂) 1, 0, 0, 1 (h₁, Q₃) 1, 0, 0, 0 (h₄, Q₄) 0, 1, 1,1 (h₃, Q₁) 0, 1, 1, 0 (h₃, Q₂) 0, 1, 0, 1 (h₃, Q₃) 0, 1, 0, 0 (h₃, Q₄)0, 0, 1, 1 (h₂, Q₂) 0, 0, 1, 0 (h₂, Q₃) 0, 0, 0, 1 (h₁, Q₁) 0, 0, 0, 0DTX

Tables 11 to 13 illustrate examples only and other mapping scheme arepossible. These examples assume that a 1 represents ACK and a 0represents NAK or DTX.

FIG. 5 illustrates possible DTX/NAK combinations for the case of a DL toUL ratio of 2. According to Table 11, the UE behavior is to transmitDTX, that is to transmit nothing, for the 00 case. FIG. 5 illustrates analternative UE behavior. The coding 00 501 represents four combinations.The first combination 511 is (DTX, DTX). The UE responds by transmittinga DTX signal 521. The second combination 512 is (DTX, NAK). The UEresponds by transmitting DTX 522. The third combination 513 is (NAK,DTX). The UE responds by transmitting DTX 523. The fourth combination514 is (NAK, DTX). The UE responds by transmitting DTX 524. Essentially,UE transmits in the ACK/NAK channel corresponding to a DL subframe whereDL grant is detected but physical downlink shared channel (PDSCH) isincorrectly decoded. In other words, the probability of UE transmittingDTX is reduced, with the expense that the number of hypothesis testingis slightly increased at NodeB.

FIG. 6 illustrates another possible set of DTX/NAK combinations for thecase of a DL to UL ratio of 2. FIG. 6 illustrates a further alternativeUE behavior to Table 11. The coding 00 601 represents four combinations.The first combination 611 is (DTX, DTX). The UE responds by transmittinga DTX signal 621. The second combination 612 is (DTX, NAK). The UEresponds by transmitting (h₁, Q₁) 622. The third combination 613 is(NAK, DTX). The UE responds by transmitting (h₂, Q₂) 623. The fourthcombination 614 is (NAK, DTX). The UE responds by transmitting (h₂, Q₂)624. Based on FIG. 6, Table 11 can be revised as Table 14.

TABLE 14 (A/N Channel, b₂ b₁ QPSK symbol) 1, 1 (h₂, Q₁) 1, 0 (h₂, Q₄) 0,1 (h₁, Q₃) 0, 0 DTX or (h₁, Q₂) or (h₂, Q₂)

FIG. 7 illustrates possible DTX/NAK combinations for the case of a DL toUL ratio of 3. According to Table 12, the UE behavior is to transmitDTX, that is to transmit nothing, for the 00 case. FIG. 7 illustrates analternative UE behavior. The coding 000 701 represents eightcombinations. The first combination 711 is (DTX, DTX, DTX). The UEresponds by transmitting a DTX signal 721. The second combination 712 is(DTX, DTX, NAK). The UE responds by transmitting a (h₁, Q₂) signal 722.The third combination 713 is (DTX, NAK, DTX). The UE responds bytransmitting a (h₂, Q₂) signal 723. The fourth combination 714 is (DTX,NAK, NAK). The UE responds by transmitting a (h₁, Q₂) signal 724. Thefifth combination 715 is (NAK, DTX, DTX). The UE responds bytransmitting a (h₃, Q₃) signal 725. The sixth combination 716 is (NAK,DTX, NAK). The UE responds by transmitting a (h₃, Q₃) signal 726. Theseventh combination 717 is (NAK, NAK, DTX). The UE responds bytransmitting a (h₂, Q₂) signal 727. The eighth combination 718 is (NAK,NAK, NAK). The UE responds by transmitting a (h₁, Q₂) signal 728. Basedon FIG. 7, Table 12 can be revised as Table 15.

TABLE 15 (A/N Channel, b₃ b₂ b₁ QPSK symbol) 1, 1, 1 (h₃, Q₁) 1, 1, 0(h₃, Q₂) 1, 0, 1 (h₁, Q₁) 1, 0, 0 (h₃, Q₄) 0, 1, 1 (h₂, Q₁) 0, 1, 0 (h₂,Q₄) 0, 0, 1 (h₁, Q₃) 0, 0, 0 DTX or (h₁, Q₂) or (h₂, Q₂) or (h₃, Q₃)

The ACK/NAK transmission mode in TDD is UE specific and RRC configured.Each UE is semi-statically configured between non-spatial multiplexingmode and spatial multiplexing mode for its DL transmissions. For anon-spatial multiplexing UE, its ACK/NAK transmission is furtherconfigured between pure bundling and no bundling. For a spatialmultiplexing UE, its ACK/NAK transmission is further configured betweenpure bundling and spatial sub-bundling.

In 3GPP LTE, a UE can bundle the multiple ACK/NAK bits corresponding tomultiple DL subframes into 1 or 2 ACK/NAK bits, and transmit the bundledACK/NAK bits in the ACK/NAK channel associated with the last detected DLsubframe. The detection of last DL grant miss replies on the ACK/NAKchannel on which the bundled ACK/NAK bits are transmitted.

When a UE needs to transmit both CQI and bundled ACK/NAK bits in thesame UL subframe, the CQI resource is used. Thus detection of last DLgrant miss is not supported. This invention proposes a few schemes tosupport the detection of last DL grant miss when UE has concurrenttransmission of ACK/NAK and CQI in TDD.

Transmitting multiple ACK/NAK bits greater than 2 in one UL subframe isalso possible to minimize the throughput loss due to bundling. A numberof assigned DL subframes may be grouped into multiple bundling groups.For example, up to 4 DL subframes may correspond to one UL subframe foreach UE in TDD configurations 2 and 4. If a UE receives DL-SCHtransmission in 4 DL subframes and must respond to the 4 assignments inone UL subframe, the UE may bundle the UL ACK/NAK bits into 2 bundles.Each bundle is associated with 2 DL subframes. Up to 4 bits of ACK/NAKare needed when greater than 1-layer transmission is used in all the DLassignments. This invention address issues of multiple ACK/NAKtransmission.

In LTE TDD, there could be 1, 2, 3, 4, or 9 DL subframes associated withone UL subframe. Therefore, the number of ACK/NAK bits to be transmittedin the UL subframe can be 1, 2, 3, 4, 6, 8, 9, or 18. Supporting such adynamic range of number of ACK/NAK is not desirable from the point ofview of the ACK/NAK detection performance. In the following, we presentour views on the design of multiple ACK/NAK transmission in TDD.

Table 16 lists the proposed number of supported multiple ACK/NAK bits.For UL subframe associated with only one DL subframe, PUCCH format 1 aor 1 b is used to transmit 1 or 2 ACK/NAK bits. For a DL to UL ratio of9, the number of DL subframes in which a UE is scheduled for unicasttransmission is limited to 4. Therefore, the number of supportedmultiple ACK/NAK bits in a configuration with a DL to UL ratio of 9 isthe same as a configuration with a DL to UL ratio of 4.

TABLE 16 Number of DL Maximum number of ACK/NAK bits subframesNon-spatial associated multiplexing Spatial multiplexing with One ULPure No Pure Sub- No subframe Bundling Bundling Bundling BundlingBundling 2 1 2 2 N/A 4 3 1 3 2 3 6 (*) 4 1 4 2 4 8 (*) 9 1 4 2 4 8 (*)(*) not applicable for concurrent transmission of ACK/NAK and CQI onPUCCH

In Table 16, pure bundling refers to bundling the ACK/NAK bitscorresponding to DL data streams across all DL subframes associated witha common UL subframe. This is illustrated in FIG. 3. FIG. 3 aillustrates an example of pure bundling with non-spatial multiplexingfor a DL to UL ratio of 4. FIG. 3 b illustrates an example of purebundling with spatial multiplexing for a DL to UL ratio of 4. Note thatdue to rank adaptation, not all DL subframes have the same number ofdata streams.

Sub-bundling is applicable for spatial multiplexing with more than 2 DLsubframes associated with a common UL subframe. Sub-bundling isperformed across spatial codewords, as shown in FIG. 4.

No-Bundling in Table 16 refers the case where all ACK/NAK bits areexplicitly transmitted without compression.

For ACK/NAK only transmission, a UE is configured by higher layer suchas RRC signaling to one three modes: Pure Bundling; Sub-Bundling; or NoBundling. Generally 2 bits are required for such configuration. If onlytwo modes are supported (Pure Bundling or No Bundling), then only 1 bitis needed because only two modes are supported for non-spatialmultiplexing in Table 16.

For concurrent transmission of ACK/NAK and CQI on PUCCH, this inventionlimits the number of ACK/NAK bits to 4. This ensures sufficientdetection performance of ACK/NAK and CQI. Therefore, spatialmultiplexing with No Bundling for DL/UL ratios of 3, 4, and 9 are notsupported for concurrent transmission of ACK/NAK and CQI. UE configuredin the No Bundling mode for ACK/NAK only transmission on PUCCH, mustfall back to either pure bundling or sub-bundling when they haveconcurrent ACK/NAK and CQI to transmit on PUCCH. This fall-back schemecan have a default mode such as always fall-back to pure bundling orsub-bundling. Alternatively, this fall-back scheme can be cell specificor UE specific. If the fall-back scheme is UE specific, additionalconfiguration bits such as 1 bit RRC signaling are needed. If thefall-back scheme is cell-specific, then it can be specified in SIB.

Non-spatial multiplexing UEs configured for No Bundling for ACK/NAK onlytransmission on PUCCH, may fall back to pure bundling when there areconcurrent ACK/NAK and CQI to transmit. Alternatively, non-spatialmultiplexing UEs configured for No Bundling for ACK/NAK onlytransmission on PUCCH do not fall back to pure bundling when there areconcurrent ACK/NAK and CQI to transmit. This fall-back scheme fornon-spatial multiplexing UEs may be cell specific or UE specific. If thefall-back scheme is UE specific, additional configuration bits such as 1bit RRC signaling are needed. If the fall-back scheme is cell-specific,then it can be specified in SIB.

For concurrent ACK/NAK and CQI transmission on PUCCH, NAK and DTX sharea common state. For a DL subframe in which no DL grant is detected by aUE, NAK (or NAK/NAK) will be transmitted corresponding to the datastream(s) on that DL subframe.

Table 17 shows QPSK mapping used in 3GPP E-UTRA. In some embodiments ofthe invention b(i) and b(i+1) are ACK/NAK bits. In some embodiments ofthe invention, either b(i) or b(i+1) or both can be ACK/NAK bit bundles.I is the in-phase and Q is the quadrature modulation components of theQPSK coding. In some notations, whatever is transmitted on Q ismultiplied with imaginary unit j. Note that √{square root over (2)}factor is for normalization. Table 17 is a permuted version of Table 7.Other permutations are possible.

TABLE 17 b(i), b(i + 1) I Q 0, 0  1/{square root over (2)}  1/{squareroot over (2)} 0, 1  1/{square root over (2)} −1/{square root over (2)}1, 0 −1/{square root over (2)}  1/{square root over (2)} 1, 1 −1/{squareroot over (2)} −1/{square root over (2)}

Subframes are numbered in monotonically increasing order. If the lastsubframe of a radio frame is k, then first subframe of the next radioframe is k+1.

This invention supports the following combinations of uplink controlinformation on PUCCH: HARQ-ACK using PUCCH format 1 a or 1 b; andHARQ-ACK using PUCCH format 1 b with channel selection. For TDD, twoACK/NAK feedback modes are supported by higher layer configuration.These include: ACK/NAK bundling; and ACK/NAK multiplexing. For TDD UL-DLconfiguration 5, only ACK/NAK bundling is supported.

TDD ACK/NAK bundling is performed per codeword across M multiple DLsubframes associated with a single UL subframe n, where M is the numberof elements in the set K defined in Table 18 by a logical AND operationof all the individual PDSCH transmission with and without correspondingphysical downlink shared channel (PDCCH) ACK/NAKs and ACK in response toPDCCH transmission indicating downlink SPS release. The bundled firstACK/NAK bit is transmitted using PUCCH format 1 a and the bundled secondACK/NAK bit is transmitted using PUCCH format 1 b.

For TDD ACK/NAK multiplexing and a subframe n with M>1, where M is thenumber of elements in the set K defined in Table 18, spatial ACK/NAKbundling across multiple codewords within a DL subframe is performed bya logical AND operation of all the corresponding individual ACK/NAKs andPUCCH format 1 b with channel selection is used. For TDD ACK/NAKmultiplexing and a subframe n with M=1, spatial ACK/NAK bundling acrossmultiple codewords within a DL subframe is not performed, one ACK/NAKbit is transmitted using PUCCH format 1 a or two ACK/NAK bits aretransmitted using respective PUCCH format 1 a and PUCCH format 1 b.

For FDD, the UE shall use PUCCH resource n_(PUCCH) ⁽¹⁾ for transmissionof HARQ-ACK in subframe n. For a PDSCH transmission indicated by thedetection of a corresponding PDCCH in subframe n-4 or for a PDCCHindicating semi-persistent scheduling (SPS) in subframe n-4, the UE usesn_(PUCCH) ⁽¹⁾=n_(CCE)+N_(PUCCH) ⁽¹⁾, where n_(CCE) is the number of thefirst CCE used for transmission of the corresponding DCI assignment andN_(PUCCH) ⁽¹⁾ is configured by higher layers.

For TDD ACK/NAK bundling or TDD ACK/NAK multiplexing and a subframe nwith M=1 where M is the number of elements in the set K defined in Table18, the UE uses PUCCH resource n_(PUCCH) ⁽¹⁾ for transmission ofHARQ-ACK in subframe n. If there is a PDSCH transmission indicated bythe detection of corresponding PDCCH or there is a PDCCH indicatingdownlink SPS release within subframe (s) n-k, where kεK and K defined inTable 18 is a set of M elements {k₀, k₁, . . . , k_(M-1)} depending onthe subframe n and the UL-DL configuration of Table 1, the UE firstselects a value p from {0, 1, 2, 3} which makes N_(p)≦n_(CCE)<N_(p+1)and uses n_(PUCCH) ⁽¹⁾=(M−m−1)×N_(p)+m×N_(p+1)+n_(CCE)N_(PUCCH) ⁽¹⁾,where N_(PUCCH) ⁽¹⁾ PUCCH is configured by higher layers,N_(p)=max{0,└[N_(RB) ^(DL)×(N_(sc) ^(RB)×p−4)]/36┘} and n_(CCE) is thenumber of the first CCE used for transmission of the corresponding PDCCHin subframe n-k_(m) and the corresponding m, where k_(m) is the smallestvalue in set K such that UE detects a PDCCH in subframe n-k_(m).

If there is only a PDSCH transmission and not a corresponding PDCCHdetected within subframe(s) n-k, where kεK and K is defined in Table 18,the value of n_(PUCCH) ⁽¹⁾ is determined according to higher layerconfiguration.

TABLE 18 UL-DL Con- Subframe n figuration 0 1 2 3 4 5 6 7 8 9 0 — — 6 —4 — — 6 — 4 1 — — 7, 6 4 — — — 7, 6 4 — 2 — — 8, 7, 4, 6 — — — — 8, 7, —— 4, 6 3 — — 7, 6, 11 6, 5 5, 4 — — — — — 4 — — 12, 8, 7, 6, 5, — — — —— — 11 4, 7 5 — — 13, 12, 9, — — — — — — — 8, 7, 5, 4, 11, 6 6 — — 7 7 5— — 7 7 —

For TDD ACK/NAK multiplexing and sub-frame n with M>1, where M is thenumber of elements in the set K defined in Table 18, then n_(PUCCH) ⁽¹⁾is the ACK/NAK resource derived from subframe n-k_(i) and HARQ-ACK(i) asthe ACK/NAK/DTX response from sub-frame n-k_(i), where k_(i)εK asdefined in Table 18 and 0≦i≦M−1 Note that n_(PUCCH,i) ⁽¹⁾ corresponds toh_(i), the ACK/NAK channel for the i-th DL subframe.

For a PDSCH transmission or a PDCCH indicating downlink SPS release insub-frame n-k_(i) where k_(i)εK the ACK/NAK resource n_(PUCCH)⁽¹⁾=(M−i−1)×N_(p)+i×N_(p+1)+n_(CCE,i)+N_(PUCCH) ⁽¹⁾, where p is selectedfrom {0, 1, 2, 3} such that N_(p)≦n_(CCE)<N_(p+1), N_(p)=max{0,└[N_(RB)^(DL)×(N_(sc) ^(RB)×p−4)]/36┘}, n_(CCE,i) is the number of the first CCEused for transmission of the corresponding PDCCH in subframe n-k_(i) andN_(PUCCH) ⁽¹⁾ is configured by higher layers.

For a PDSCH transmission where there is not a corresponding PDCCHdetected in subframe n-k_(i), the value of n_(PUCCH) ⁽¹⁾ is determinedaccording to higher layer configuration.

The UE shall transmit b(0), b(1) on an ACK/NAK resource n_(PUCCH) ⁽¹⁾ insub-frame n using PUCCH format 1 b. The value of b(0), b(1) and theACK/NAK resource n_(PUCCH) ⁽¹⁾ are generated by channel selectionaccording to Table 19 for M=2, Table 20 for M=3 and Table 21 for M=4. InTables 19, 20 and 21 if b(0), b(1) is N/A, then the UE does not transmitan ACK/NAK response in sub-frame n.

Table 19 lists the ACK/NAK transmission multiplexing for M=2.

TABLE 19 HARQ-ACK(0), HARQ-ACK(1) n_(PUCCH) ⁽¹⁾ b(0), b(1) ACK, ACKn_(PUCCH, 1) ⁽¹⁾ 1, 1 ACK, NAK/DTX n_(PUCCH, 0) ⁽¹⁾ 0, 1 NAK/DTX, ACKn_(PUCCH, 1) ⁽¹⁾ 0, 0 NAK/DTX, NAK n_(PUCCH, 1) ⁽¹⁾ 1, 0 NAK, DTXn_(PUCCH, 0) ⁽¹⁾ 1, 0 DTX, DTX N/A N/A

Table 20 lists the ACK/NAK transmission multiplexing for M=3.

TABLE 20 HARQ-ACK(0), HARQ-ACK(1), HARQ-ACK(2) n_(PUCCH) ⁽¹⁾ b(0), b(1)ACK, ACK, ACK n_(PUCCH, 2) ⁽¹⁾ 1, 1 ACK, ACK, NAK/DTX n_(PUCCH, 1) ⁽¹⁾1, 1 ACK, NAK/DTX, ACK n_(PUCCH, 0) ⁽¹⁾ 1, 1 ACK, NAK/DTX, NAK/DTXn_(PUCCH, 0) ⁽¹⁾ 0, 1 NAK/DTX, ACK, ACK n_(PUCCH, 2) ⁽¹⁾ 1, 0 NAK/DTX,ACK, NAK/DTX n_(PUCCH, 1) ⁽¹⁾ 0, 0 NAK/DTX, NAK/DTX, ACK n_(PUCCH, 2)⁽¹⁾ 0, 0 DTX, DTX, NAK n_(PUCCH, 2) ⁽¹⁾ 0, 1 DTX, NAK, NAK/DTXn_(PUCCH, 1) ⁽¹⁾ 1, 0 NAK, NAK/DTX, NAK/DTX n_(PUCCH, 0) ⁽¹⁾ 1, 0 DTX,DTX, DTX N/A N/A

Table 21 lists the ACK/NAK transmission multiplexing for M=4.

TABLE 21 HARQ-ACK(0), HARQ-ACK(1), HARQ-ACK(2), HARQ-ACK(3) n_(PUCCH)⁽¹⁾ b(0), b(1) ACK, ACK, ACK, ACK n_(PUCCH, 1) ⁽¹⁾ 1, 1 ACK, ACK, ACK,NAK/DTX n_(PUCCH, 1) ⁽¹⁾ 1, 0 NAK/DTX, NAK/DTX, NAK, DTX n_(PUCCH, 2)⁽¹⁾ 1, 1 ACK, ACK, NAK/DTX, ACK n_(PUCCH, 1) ⁽¹⁾ 1, 0 NAK, DTX, DTX, DTXn_(PUCCH, 0) ⁽¹⁾ 1, 0 ACK, ACK, NAK/DTX, NAK/DTX n_(PUCCH, 1) ⁽¹⁾ 1, 0ACK, NAK/DTX, ACK, ACK n_(PUCCH, 3) ⁽¹⁾ 0, 1 NAK/DTX, NAK/DTX, NAK/DTX,NAK n_(PUCCH, 3) ⁽¹⁾ 1, 1 ACK, NAK/DTX, ACK, NAK/DTX n_(PUCCH, 2) ⁽¹⁾ 0,1 ACK, NAK/DTX, NAK/DTX, ACK n_(PUCCH, 0) ⁽¹⁾ 0, 1 ACK, NAK/DTX,NAK/DTX, NAK/DTX n_(PUCCH, 0) ⁽¹⁾ 1, 1 NAK/DTX, ACK, ACK, ACKn_(PUCCH, 3) ⁽¹⁾ 0, 1 NAK/DTX, NAK, DTX, DTX n_(PUCCH, 1) ⁽¹⁾ 0, 0NAK/DTX, ACK, ACK, NAK/DTX n_(PUCCH, 2) ⁽¹⁾ 1, 0 NAK/DTX, ACK, NAK/DTX,ACK n_(PUCCH, 3) ⁽¹⁾ 1, 0 NAK/DTX, ACK, NAK/DTX, NAK/DTX n_(PUCCH, 1)⁽¹⁾ 0, 1 NAK/DTX, NAK/DTX, ACK, ACK n_(PUCCH, 3) ⁽¹⁾ 0, 1 NAK/DTX,NAK/DTX, ACK, NAK/DTX n_(PUCCH, 2) ⁽¹⁾ 0, 0 NAK/DTX, NAK/DTX, NAK/DTX,ACK n_(PUCCH, 3) ⁽¹⁾ 0, 0 DTX, DTX, DTX, DTX N/A N/A

1. A method of responding in a wireless user equipment (UE) with anacknowledge (ACK) or non-acknowledge (NAK) to a downlink (DL)communications from a base station using frames where at least oneuplink (UL) is assigned a subframe to respond to a plurality of DLassigned subframes, comprising the steps of: generating an ACK responseat the UE to each DL communication correctly received; generating a NAKresponse at the UE to each DL communication not correctly received; fora UL subframe assigned to respond to communications on plural DLsubframes logically combining plural ACK/NAK responses into a singlebundled response; and transmitting ACK/NAK responses from the UE to thebase station including transmitting a bundled response.
 2. The method ofclaim 1, wherein: said step of logically combining plural ACK/NAKresponses produces a bit in a first digital state if all said pluralACK/NAK responses are ACKs and in a second opposite digital state if anyof said ACK/NAK responses is a NAK.
 3. The method of claim 1, wherein:said step of transmitting transmits a maximum number of multiple ACK/NAKbits of in a single UL subframe of
 4. 4. The method of claim 1, wherein:the DL communications are transmitted in a single input, multiple output(SIMO) transmission mode; a single UL subframe is assigned to respond tocommunications from 9 DL subframes; said step of logically combininglogically combines ACK/NAK responses to DL communications in a firstfive subframes into a first bit and logically combines ACK/NAK responsesto DL communications in a next four subframes into a second bit.
 5. Themethod of claim 1, wherein: the DL communications are transmitted in asingle input, multiple output (SIMO) transmission mode; a single ULsubframe is assigned to respond to communications from 9 DL subframes;and said step of logically combining logically combines ACK/NAKresponses to DL communications in a first four subframes into a firstbit and logically combines ACK/NAK responses to DL communications in anext five subframes into a second bit.
 6. The method of claim 1,wherein: the DL communications are transmitted in a multiple input,multiple output (MIMO) transmission mode; said step of logicallycombining logically combines ACK/NAK responses to DL communications in asingle data stream for plural DL communication in correspondingsubframes into a single ACK/NAK bit.
 7. The method of claim 1, wherein:the DL communications are transmitted in a multiple input, multipleoutput (MIMO) transmission mode; said step of logically combininglogically combines ACK/NAK responses to DL communications in multipledata streams into a single ACK/NAK bit.
 8. The method of claim 1,wherein: said step of transmitting employs one of physical uplinkcontrol channel (PUCCH) format 1 a and 1 b.
 9. The method of claim 8,wherein: said step of transmitting employs time division duplex (TDD).10. The method of claim 1, wherein: said step of logically combiningplural ACK/NAK responses is specified the same for each UE in aparticular cell corresponding to a particular base station.
 11. Themethod of claim 1, wherein: said step of logically combining pluralACK/NAK responses is specified for each UE.
 12. The method of claim 1,further comprising: generating a discontinuous transmission (DTX) signalat the UE when the UE misses a DL grant in a corresponding DL subframe.13. The method of claim 12, wherein: said step of logically combiningplural ACK/NAK responses includes logically combining any relevant DTXsignals.
 14. The method of claim 13, wherein: a single UL subframe isassigned to respond to two DL subframes; said step of logicallycombining includes generating two bit signals b₁ and b₂ corresponding tosaid ACK/NAK responses for said two DL subframes; and said transmittingstep includes coding the two bit signals as follows: (A/N Channel, b₂ b₁QPSK symbol) 0, 0 (h₂, Q₁) 0, 1 (h₂, Q₂) 1, 0 (h₁, Q₃) 1, 1 (h₁, Q₄) orDTX

where: h_(i) is the ACK/NAK channel associated with the i-th DLsubframe; Q₁ is −1; Q₂ is √{square root over (−1)}; Q₃ is −√{square rootover (−1)}; and Q₄ is
 1. 15. The method of claim 13, wherein: a singleUL subframe is assigned to respond to two DL subframes; said step oflogically combining includes generating two bit signals b₁ and b₂corresponding to said ACK/NAK responses for said two DL subframes; andsaid transmitting step includes coding the two bit signals as follows:(A/N Channel, b₂ b₁ QPSK symbol) 0, 0 (h₂, Q₁) 0, 1 (h₂, Q₄) 1, 0 (h₁,Q₃) 1, 1 (h₁, Q₂) or DTX

where: h_(i) is the ACK/NAK channel associated with the i-th DLsubframe; Q₁ is −1; Q₂ is √{square root over (−1)}; Q₃ is −√{square rootover (−1)}; and Q₄ is
 1. 16. The method of claim 13, wherein: a singleUL subframe is assigned to respond to two DL subframes; said step oflogically combining includes generating two bit signals b₁ and b₂corresponding to said ACK/NAK responses for said two DL subframes; andsaid transmitting step includes coding the two bit signals as follows:(A/N Channel, b₂ b₁ QPSK symbol) 1, 1 (h₂, Q₁) 1, 0 (h₂, Q₄) 0, 1 (h₁,Q₃) 0, 0 DTX

where: h_(i) is the ACK/NAK channel associated with the i-th DLsubframe; Q₁ is −1; Q₂ is √{square root over (−1)}; Q₃ is −√{square rootover (−1)}; and Q₄ is
 1. 17. The method of claim 13, wherein: a singleUL subframe is assigned to respond to two DL subframes; said step oflogically combining includes generating two bit signals b₁ and b₂corresponding to said ACK/NAK responses for said two DL subframes; andsaid transmitting step includes coding the two bit signals as follows:(A/N Channel, b₂ b₁ QPSK symbol) 1, 1 (h₂, Q₁) 1, 0 (h₂, Q₄) 0, 1 (h₁,Q₃) 0, 0 DTX or (h₁, Q₂) or (h₂, Q₂)

where: h_(i) is the ACK/NAK channel associated with the i-th DLsubframe; Q₁ is −1; Q₂ is √{square root over (−1)}; Q₃ is −√{square rootover (−1)}; and Q₄ is
 1. 18. The method of claim 13, wherein: a singleUL subframe is assigned to respond to three DL subframes; said step oflogically combining includes generating three bit signals b₁, b₂ and b₃corresponding to said ACK/NAK responses for said three DL subframes; andsaid transmitting step includes coding the three bit signals as follows:(A/N Channel, b₃ b₂ b₁ QPSK symbol) 0, 0, 0 (h₃, Q₁) 0, 0, 1 (h₃, Q₂) 0,1, 0 (h₃, Q₃) 0, 1, 1 (h₃, Q₄) 1, 0, 0 (h₂, Q₁) 1, 0, 1 (h₂, Q₄) 1, 1, 0(h₁, Q₁) 1, 1, 1 (h₁, Q₄) or DTX

where: h_(i) is the ACK/NAK channel associated with the i-th DLsubframe; Q₁ is −1; Q₂ is √{square root over (−1)}; Q₃ is −√{square rootover (−1)}; and Q₄ is
 1. 19. The method of claim 13, wherein: a singleUL subframe is assigned to respond to three DL subframes; said step oflogically combining includes generating three bit signals b₁, b₂ and b₃corresponding to said ACK/NAK responses for said three DL subframes; andsaid transmitting step includes coding the three bit signals as follows:(A/N Channel, b₃ b₂ b₁ QPSK symbol) 0, 0, 0 (h₃, Q₁) 0, 0, 1 (h₃, Q₂) 0,1, 0 (h₃, Q₃) 0, 1, 1 (h₃, Q₄) 1, 0, 0 (h₂, Q₁) 1, 0, 1 (h₂, Q₄) 1, 1, 0(h₁, Q₃) 1, 1, 1 (h₁, Q₂) or DTX

where: h_(i) is the ACK/NAK channel associated with the i-th DLsubframe; Q₁ is −1; Q₂ is √{square root over (−1)}; Q₃ is −√{square rootover (−1)}; and Q₄ is
 1. 20. The method of claim 13, wherein: a singleUL subframe is assigned to respond to three DL subframes; said step oflogically combining includes generating three bit signals b₁, b₂ and b₃corresponding to said ACK/NAK responses for said three DL subframes; andsaid transmitting step includes coding the three bit signals as follows:(A/N Channel, b₃ b₂ b₁ QPSK symbol) 1, 1, 1 (h₃, Q₁) 1, 1, 0 (h₃, Q₂) 1,0, 1 (h₃, Q₃) 1, 0, 0 (h₃, Q₄) 0, 1, 1 (h₂, Q₁) 0, 1, 0 (h₂, Q₄) 0, 0, 1(h₁, Q₃) 0, 0, 0 DTX

where: h_(i) is the ACK/NAK channel associated with the i-th DLsubframe; Q₁ is −1; Q₂ is √{square root over (−1)}; Q₃ is −√{square rootover (−1)}; and Q₄ is
 1. 21. The method of claim 13, wherein: a singleUL subframe is assigned to respond to three DL subframes; said step oflogically combining includes generating three bit signals b₁, b₂ and b₃corresponding to said ACK/NAK responses for said three DL subframes; andsaid transmitting step includes coding the three bit signals as follows:(A/N Channel, b₃ b₂ b₁ QPSK symbol) 1, 1, 1 (h₃, Q₁) 1, 1, 0 (h₃, Q₂) 1,0, 1 (h₁, Q₁) 1, 0, 0 (h₃, Q₄) 0, 1, 1 (h₂, Q₁) 0, 1, 0 (h₂, Q₄) 0, 0, 1(h₁, Q₃) 0, 0, 0 DTX or (h₁, Q₂) or (h₂, Q₂) or (h₃, Q₃)

where: h_(i) is the ACK/NAK channel associated with the i-th DLsubframe; Q₁ is −1; Q₂ is √{square root over (−1)}; Q₃ is −√{square rootover (−1)}; and Q₄ is
 1. 22. The method of claim 13, wherein: a singleUL subframe is assigned to respond to four DL subframes; said step oflogically combining includes generating four bit signals b₁, b₂, b₃ andb₄ corresponding to said ACK/NAK responses for said four DL subframes;and said transmitting step includes coding the four bit signals asfollows: (A/N Channel, b₄ b₃ b₂ b₁ QPSK symbol) 0, 0,
 0. 0 (h₂, Q₁) 0,0, 0, 1 (h₂, Q₃) 0, 0, 1, 0 (h₄, Q₁) 0, 0, 1, 1 (h₄, Q₃) 0, 1, 0, 0 (h₁,Q₂) 0, 1, 0, 1 (h₄, Q₂) 0, 1, 1, 0 (h₁, Q₃) 0, 1, 1, 1 (h₄, Q₄) 1, 0, 0,0 (h₃, Q₁) 1, 0, 0, 1 (h₃, Q₂) 1, 0, 1, 0 (h₃, Q₃) 1, 0, 1, 1 (h₃, Q₄)1, 1, 0, 0 (h₂, Q₂) 1, 1, 0, 1 (h₂, Q₄) 1, 1, 1, 0 (h₁, Q₁) 1, 1, 1, 1(h₁, Q₄) or DTX

where: h_(i) is the ACK/NAK channel associated with the i-th DLsubframe; Q₁ is −1; Q₂ is √{square root over (−1)}; Q₃ is −√{square rootover (−1)}; and Q₄ is
 1. 23. The method of claim 13, wherein: a singleUL subframe is assigned to respond to four DL subframes; said step oflogically combining includes generating four bit signals b₁, b₂, b₃ andb₄ corresponding to said ACK/NAK responses for said four DL subframes;and said transmitting step includes coding the four bit signals asfollows: (A/N Channel, b₄ b₃ b₂ b₁ QPSK symbol) 0, 0, 0, 0 (h₂, Q₁) 0,0, 0, 1 (h₂, Q₄) 0, 0, 1, 0 (h₄, Q₁) 0, 0, 1, 1 (h₄, Q₃) 0, 1, 0, 0 (h₁,Q₂) 0, 1, 0, 1 (h₄, Q₂) 0, 1, 1, 0 (h₁, Q₃) 0, 1, 1, 1 (h₄, Q₄) 1, 0, 0,0 (h₃, Q₁) 1, 0, 0, 1 (h₃, Q₂) 1, 0, 1, 0 (h₃, Q₃) 1, 0, 1, 1 (h₃, Q₄)1, 1, 0, 0 (h₂, Q₂) 1, 1, 0, 1 (h₂, Q₃) 1, 1, 1, 0 (h₁, Q₁) 1, 1, 1, 1(h₁, Q₄) or DTX

where: h_(i) is the ACK/NAK channel associated with the i-th DLsubframe; Q₁ is −1; Q₂ is √{square root over (−1)}; Q₃ is −√{square rootover (−1)}; and Q₄ is
 1. 24. The method of claim 13, wherein: a singleUL subframe is assigned to respond to four DL subframes; said step oflogically combining includes generating four bit signals b₁, b₂, b₃ andb₄ corresponding to said ACK/NAK responses for said four DL subframes;and said transmitting step includes coding the four bit signals asfollows: (A/N Channel, b₄ b₃ b₂ b₁ QPSK symbol) 1, 1, 1, 1 (h₂, Q₁) 1,1, 1, 0 (h₂, Q₄) 1, 1, 0, 1 (h₄, Q₁) 1, 1, 0, 0 (h₄, Q₃) 1, 0, 1, 1 (h₁,Q₂) 1, 0, 1, 0 (h₄, Q₂) 1, 0, 0, 1 (h₁, Q₃) 1, 0, 0, 0 (h₄, Q₄) 0, 1, 1,1 (h₃, Q₁) 0, 1, 1, 0 (h₃, Q₂) 0, 1, 0, 1 (h₃, Q₃) 0, 1, 0, 0 (h₃, Q₄)0, 0, 1, 1 (h₂, Q₂) 0, 0, 1, 0 (h₂, Q₃) 0, 0, 0, 1 (h₁, Q₁) 0, 0, 0, 0DTX

where: h_(i) is the ACK/NAK channel associated with the i-th DLsubframe; Q₁ is −1; Q₂ is √{square root over (−1)}; Q₃ is −√{square rootover (−1)}; and Q₄ is
 1. 25. The method of claim 13, wherein: a singleUL subframe is assigned to respond to two DL subframes; said step oflogically combining includes generating bit signals b(0) and b(1) andselecting an ACK/NAK response channel n_(PUCCH,i) ⁽¹⁾ corresponding tosaid ACK/NAK responses for said two DL subframes as follows:HARQ-ACK(0), HARQ-ACK(1) n_(PUCCH) ⁽¹⁾ b(0), b(1) ACK, ACK n_(PUCCH, 1)⁽¹⁾ 1, 1 ACK, NAK/DTX n_(PUCCH, 0) ⁽¹⁾ 0, 1 NAK/DTX, ACK n_(PUCCH, 1)⁽¹⁾ 0, 0 NAK/DTX, NAK n_(PUCCH, 1) ⁽¹⁾ 1, 0 NAK, DTX n_(PUCCH, 0) ⁽¹⁾ 1,0 DTX, DTX N/A N/A


26. The method of claim 13, wherein: a single UL subframe is assigned torespond to three DL subframes; said step of logically combining includesgenerating bit signals b(0) and b(1) and selecting an ACK/NAK responsechannel n_(PUCCH,i) ⁽¹⁾ corresponding to said ACK/NAK responses for saidthree DL subframes as follows: HARQ-ACK(0), HARQ-ACK(1), HARQ-ACK(2)n_(PUCCH) ⁽¹⁾ b(0), b(1) ACK, ACK, ACK n_(PUCCH, 2) ⁽¹⁾ 1, 1 ACK, ACK,NAK/DTX n_(PUCCH, 1) ⁽¹⁾ 1, 1 ACK, NAK/DTX, ACK n_(PUCCH, 0) ⁽¹⁾ 1, 1ACK, NAK/DTX, NAK/DTX n_(PUCCH, 0) ⁽¹⁾ 0, 1 NAK/DTX, ACK, ACKn_(PUCCH, 2) ⁽¹⁾ 1, 0 NAK/DTX, ACK, NAK/DTX n_(PUCCH, 1) ⁽¹⁾ 0, 0NAK/DTX, NAK/DTX, ACK n_(PUCCH, 2) ⁽¹⁾ 0, 0 DTX, DTX, NAK n_(PUCCH, 2)⁽¹⁾ 0, 1 DTX, NAK, NAK/DTX n_(PUCCH, 1) ⁽¹⁾ 1, 0 NAK, NAK/DTX, NAK/DTXn_(PUCCH, 0) ⁽¹⁾ 1, 0 DTX, DTX, DTX N/A N/A


27. The method of claim 13, wherein: a single UL subframe is assigned torespond to four DL subframes; said step of logically combining includesgenerating bit signals b(0) and b(1) and selecting an ACK/NAK responsechannel n_(PUCCH) ⁽¹⁾ corresponding to said ACK/NAK responses for saidfour DL subframes as follows: HARQ-ACK(0), HARQ-ACK(1), HARQ-ACK(2),HARQ-ACK(3) n_(PUCCH) ⁽¹⁾ b(0), b(1) ACK, ACK, ACK, ACK n_(PUCCH, 1) ⁽¹⁾1, 1 ACK, ACK, ACK, NAK/DTX n_(PUCCH, 1) ⁽¹⁾ 1, 0 NAK/DTX, NAK/DTX, NAK,DTX n_(PUCCH, 2) ⁽¹⁾ 1, 1 ACK, ACK, NAK/DTX, ACK n_(PUCCH, 1) ⁽¹⁾ 1, 0NAK, DTX, DTX, DTX n_(PUCCH, 0) ⁽¹⁾ 1, 0 ACK, ACK, NAK/DTX, NAK/DTXn_(PUCCH, 1) ⁽¹⁾ 1, 0 ACK, NAK/DTX, ACK, ACK n_(PUCCH, 3) ⁽¹⁾ 0, 1NAK/DTX, NAK/DTX, NAK/DTX, NAK n_(PUCCH, 3) ⁽¹⁾ 1, 1 ACK, NAK/DTX, ACK,NAK/DTX n_(PUCCH, 2) ⁽¹⁾ 0, 1 ACK, NAK/DTX, NAK/DTX, ACK n_(PUCCH, 0)⁽¹⁾ 0, 1 ACK, NAK/DTX, NAK/DTX, NAK/DTX n_(PUCCH, 0) ⁽¹⁾ 1, 1 NAK/DTX,ACK, ACK, ACK n_(PUCCH, 3) ⁽¹⁾ 0, 1 NAK/DTX, NAK, DTX, DTX n_(PUCCH, 1)⁽¹⁾ 0, 0 NAK/DTX, ACK, ACK, NAK/DTX n_(PUCCH, 2) ⁽¹⁾ 1, 0 NAK/DTX, ACK,NAK/DTX, ACK n_(PUCCH, 3) ⁽¹⁾ 1, 0 NAK/DTX, ACK, NAK/DTX, NAK/DTXn_(PUCCH, 1) ⁽¹⁾ 0, 1 NAK/DTX, NAK/DTX, ACK, ACK n_(PUCCH, 3) ⁽¹⁾ 0, 1NAK/DTX, NAK/DTX, ACK, NAK/DTX n_(PUCCH, 2) ⁽¹⁾ 0, 0 NAK/DTX, NAK/DTX,NAK/DTX, ACK n_(PUCCH, 3) ⁽¹⁾ 0, 0 DTX, DTX, DTX, DTX N/A N/A


28. The method of claim 1, wherein: the DL communications is capable ofoperating in one of a single input, multiple output (SIMO) mode or amultiple input, multiple output (MIMO) mode; said step of logicallycombining plural ACK/NAK responses generates a number of ACK/NAK bits asfollows: Number of DL subframes associated Number of ACK/NAK bits withone UL subframe SIMO MIMO 1 1 2 2 2 4 3 3 3 4 4 4 9 2 4


29. The method of claim 1, further comprising: operating the DLcommunications in a multiple input, multiple output (MIMO) mode; saidstep of logically combining plural ACK/NAK responses generates a numberof ACK/NAK bits as follows: Number of DL Maximum number of ACK/NAK bitssubframes Non-spatial Spatial associated multiplexing multiplexing withone UL Pure No Pure Spatial Sub- subframe Bundling Bundling Bundlingbundling 2 1 2 2 2 3 1 3 2 3 4 1 4 2 4 9 1 4 2 4

where: spatial sub-bundling is bundling performed across MIMO codewordsper DL subframe.
 30. The method of claim 1, further comprising:operating the DL communications in a multiple input, multiple output(MIMO) mode; said step of logically combining plural ACK/NAK responsesgenerates a number of ACK/NAK bits as follows: Number of DL Maximumnumber of ACK/NAK bits subframes Non-spatial associated multiplexingSpatial multiplexing with One UL Pure No Pure Sub- No subframe BundlingBundling Bundling Bundling Bundling 2 1 2 2 N/A 4 3 1 3 2 3 6 (*) 4 1 42 4 8 (*) 9 1 4 2 4 8 (*) (*) not applicable for concurrent transmissionof ACK/NAK and CQI on PUCCH

where: spatial sub-bundling is bundling performed across MIMO codewordsper DL subframe.
 31. The method of claim 1, wherein: said step oflogically combining plural ACK/NAK responses is performed per codewordacross M multiple DL subframes associated with a single UL subframe n,where M is the number of elements in the set K defined as: UL-DL Con-Subframe n figuration 0 1 2 3 4 5 6 7 8 9 0 — — 6 — 4 — — 6 — 4 1 — — 7,6 4 — — — 7, 6 4 — 2 — — 8, 7, 4, 6 — — — — 8, 7, — — 4, 6 3 — — 7, 6,11 6, 5 5, 4 — — — — — 4 — — 12, 8, 7, 6, 5, — — — — — — 11 4, 7 5 — —13, 12, 9, — — — — — — — 8, 7, 5, 4, 11, 6 6 — — 7 7 5 — — 7 7 —